Vehicles having electrically controlled automatic level-correcting suspension



2, 1966 F. s. ALLINQUANT 3,264,003

VEHICLES HAVING ELECTRICALLY CONTROLLED AUTOMATIC LEVELCORRECTINGSUSPENSION Original Filed Nov. 29, 1963 2 Sheets-Sheet 1 ATT' NEYS? 1966s ALLINQUANT 3 264,008

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ATToRN YS United States Patent Ofi ice 3,264,008 Patented August 2, 19663,264,008 VEHICLES HAVING ELECTRICALLY CON- TROLLED AUTOMATICLEVEL-CORRECT- ENG SUSPENSXON Fernand Stanislas Allinquant, 53 Ave. LeNotre, Sceaux, France Continuation of appiication Ser. No. 326,952, Nov.29, 1963. This application Sept. 28, 1965, Ser. No. 490,790 Claimspriority, application France Dec. 5, 1962, 917,637, Patent 1,379,617Claims. (Cl. 280-6) This is a continuation of my application Serial No.326,952 filed November 29, 1963.

In my US. patent application No. 158,740 filed on November 12, 1961, nowUS. Patent No. 3,122,379, there are described level-correctingassemblies applicable, in particular, to vehicles having oleopneumaticsuspension and using an electrical device for height-detection and forcontrolling the feeding of the suspension. Such feeding, which takesplace only intermittently, is effected under the control of voltagepulses triggered by the accelerator pedal, means for the transfer of afluid between two chambers in which different pressures prevail beingadapted to be energized during the duration of the pulses through theintermediary of movable contacts responsive to the position of thewheels or other unsuspended parts of the vehicle with respect to thesuspended body or chassis of the latter. Provision if further made forprolonging the effect of such a pulse by means of a re-feed devicewhereby, after a movement which has produced a pulse, the said transfermeans operates continuously, whatever the position of the accelerator,until a correct level is obtained.

This invention relates to an electrical feeding device of theabove-mentioned re-feed type which is easy to produce and to mount on avehicle, irrespective of the number of transfer means. This object canbe reached, according to the invention, by use of a single re-feed relaywhich can be energized by any transfer means set into operation byimpulse producing means. The refeed relay has an energizing coilconnected through an electrical unidirectional element such as a diodein parallel with each of said transfer means.

According to an advantageous optional feature of the invention, at leastone of the transfer means, which required an electrical currentexceeding the rating of the associated unidirectional current flowmeans, is fed through the medium of a power relay associated with there-feed relay and directly fed by the electrical generator through thegeneral vehicle switch.

A more particular object of this invention is to avoid unduelevel-correction, during a temporary stop at a traffic light forexample, an automatic suspension functioning in bad conditions, whenbrakes are applied. In one embodiment of the invention, this object isreached by mounting impulse producing means comprising a main switchactuated by the accelerator pedal and delaying means, in the circuitwhich leads from the electrical generator to the transfer means and tothe energizing coil of the re-feed relay. This embodiment is speciallydesigned to break the circuit established by the accelerator pedal aftera certain period, whatever the total time during which the drivers footbears on the pedal may be. The circuit comprising the re-feed relaymobile armature is by-passed by said delaying means but includes themain switch.

In another embodiment, the main switch and the delaying meansdetermining the time and the total duration of the correction initiatingimpulses are always connected in a series yet are by-passed by :are-feed circuit comprising a re-feed relay mobile armature.

The invention will be described below with reference to the accompanyingdrawings which show by way of example forms of device, in which:

FIG. 1 is a diagram, with partial section, of a first embodiment of alevel-correcting device associated with the suspension elements of a setof wheels of a vehicle; and

FIG. 2 is a diagram, with partial section, of a second embodiment of alevel-correcting device associated with the suspension elements of a setof wheels of a vehicle.

In FIG. 1, there is shown an oleopneumatic suspension unit 1 associatedwith a wheel 2 which is carried by an arm 3 and the associatedlevel-correcting device which carries out electrical height detectionand controls the feeding of the suspension system. Like wheels andsuspension systems have been schematically shown and are referred towith prime numbers.

The suspension unit 1 comprises, for example, two chambers 4 and5 foreach wheel unit, which chambers are filled with gas under pressure andwhich are enabled to communicate with one another by means of transfermeans such an electric valve 6 and a compressor 7, which latter isdriven by an electric motor 8. The compressor 7 is advantageously of atype employing pistons but, for the sake of simplicity, it is shown inthe drawings as a volumetric machine embodying gear wheels.

The transfer means 6 and 7 are under the control of at least oneheight-detecting contact 9 which is connected to a wheel 2 of thevehicle and permits one or the other of them to be energized when thelevel of the vehicle is temporarily incorrect. They may each have anindicator lamp such as 6a associated therewith.

The feed-controlling device proper comprises an electrical generator 10,a general switch 11 actuated by a key, for instance, a main switch 12actuated by the accelerator pedal 13, so as to be closed beyond apredetermiend point of the travel of the latter, a slow-acting relay 14and a re-feed relay 15.

The slow-acting relay 14, which is known per se, is disposed immediatelyon the negative side of the main switch 12 and is normally closed. Ithas an energizing circuit comprising an induction coil 16a and acondenser 16b connected in parallel, and a resistance 17 is disposed inseries with the said energizing circuit and controls the intensity ofthe current passing through the latter.

The re-feed relay 15 has two main terminals 18 and 19 connected by anarmature 20 which is normally held open by a spring 20a, but it subjectto the action of an energizing coil 21; the latter terminal is connectedto the various transfer means by connections 22a, 22b, 22c, 22d, each ofwhich includes a unidirectional connecting element 24 such as a diode.Each transfer means would be connected in parallel between, heightdetecting contact 9 and the ground-return to a connection such as 22b.

The motor and compressor set 7 and 8 requiring a rather substantialcurrent intensity, it is supplied through the intermediary of a powerrelay 23', the armature of which bears the reference 230 and whoseenergizing coil 23a is joined to the connection 22a, the supply terminal23b for the motor 8 then being connected to a point located between thegeneral switch 11 and the main switch 12 actuated by the acceleratorpedal.

It will be observed on FIG. 1 that the terminal 18 of the re-feed relayis connected to the negative side of said main switch 12. All thecircuits are moreover of the single-wire ground-return type, such as arecurrently used in the electrical systems of motor vehicles.

The operation of a device of this kind is as follows:

After the main switch 11 has been closed, the starting of the vehicleengine is accompanied by depression of the accelerator pedal 13, whichcloses the contact 12. The resulting energization of the circuits 16a,16b by way of the resistance 17 results in the opening of theslow-acting relay 14 after a time delay which, in practice, is fixed.If, during this time, there is any incorrectness in the level of thevehicle, there will be upward or downward closing of the contact 9 andenergization of the transfer means of the suspension of the vehicle(that is to say, the electric valve 6 in the drawing), possibly withclosing of a relay such as 23. The diodes 24 or other. unidirectionalconnecting elements 24 provided in the connections 22a, 22b, 22c, 22dprevent stray simultaneous energization of several transfer means.

When one of the connections 22a, 22b, 22c, 22d energizes the coil 22 ofthe re-feed relay, the armature 20 connects the terminals 18 and 19, theresult of which is that the transfer means hereabove mentioned can stilloperate after the opening of the slow-acting relay 14 as long as thecontact 9 and, of course, the switch 12 remain closed.

During the whole operation of the transfer means, the masses of gascontained in the respective chambers 4 and therefore vary in the sensewhich tends to restore the normal level of the vehicle.

In FIG. 2, there is shown an alternative embodiment according to whichthe terminal 18 of the re-feed relay is connected to an electricalgenerator in parallel with the switch 12 instead of in series with thelatter. The embodiment of the FIG. 1 is advantageous, however, in thatit avoids any premature operation of the levelcorrecting device during atemporary stop. In a vehicle having provision for level correction, theapplication of the brakes in the case of such a stop can produceconsiderable strain in the suspension. However, as the accelerationpedal cannot remain depressed without the engine racing, the switch 12is therefore necessarily opened.

The device described can be easily adapted to the characteristics of anyparticular vehicle and even, if required, of the individual driver, byadjustment of the closing travel of the switch 12 and adjustment of thedelay time of the relay 14. This provides final adjustment of that partof the driving time during which the electrical levelcorrecting deviceproper 6, 7, 8, 9 happens to be actuated by jolting or any other cause,for the purpose of restoring the normal level of the vehicle bysuccessive pulses or stages. Light indicators or signals such as 6aenable the driver to obtain, if desired, an idea of the frequency of thecorrections and to check the functioning of the suspension.

It is obvious that the invention is not limited to the embodiments whichhave been particularly described, but that it also covers modificationswhich can be obtained, within the scope of the appended claims by theuse of equivalent technical means.

What is claimed is:

1.- In a vehicle having a body, an accelerator pedal, wheels and a fluidsuspension system, at least one suspen sion element associated with eachwheel for supporting said body, electrically actuated transfer means forcontrolling an active fluid mass enclosed within said element, anelectrical level-correcting device comprising, in combination, awheel-switch associated with each wheel for detecting the positionthereof relative to said body and for controlling thereby the actuationof said transfer means, impulse-producing means comprising switchingmeans and an electric power source, said impulse-producing meansconnecting said wheel switch to said electric power source only atselective intervals, a re-feed relay of the normally open type having anenergizing coil and a mobile armature actuatable by said coil, saidarmature in its closed position by-passing said impulse-producing meansby closing a circuit between said power source and said wheel switch, atleast one unidirectional current flow means connecting said energizingcoil to each and every one of said transfer means for providingenergiaztion of said coil at the same time as any one of said transfermeans but preventing stray simultaneous energization of several transfermeans.

2. An electrical level-correcting device according to claim 1 whereinsaid unidirectional current flow means are diodes.

3. An electrical level-correcting device according to claim 1 whereinsaid switching means comprises a main switch and a normally closedslow-acting relay connected in series between said main switch and saidtransfer means, said main switch being actuated by said acceleratorpedal.

4. In a vehicle having a body, an accelerator pedal, wheels, and a fluidsuspension system, at least one suspension element associated with eachwheel for supporting said body, electrically actuated transfer means forcontrolling an active fluid mass enclosed within said element, anelectrical level-correcting device comprising in combination, awheel-switch associated with each wheel for detecting the positionthereof relative to said body and for controlling thereby the actuationof said transfer means, impulse-producing means comprising switchingmeans and an electric power source, said impulse-producing meansconnecting said wheel switch to said electric power source only atselective intervals, a re-feed relay of the normally open type having anenergizing coil and a mobile armature actuatable by said coil, saidarmature in its closedrposition closing a circuit between said powersource and said wheel switch, at least one unidirectional current flowmeans connecting said energizing coil to each and every one of saidtransfer means for providing energization of said coil at the same timeas any one of said transfer means but preventing stray simultaneousenergization of several transfer means, a power relay for the purpose ofenergizing one of said transfer means necessitating an electricalcurrent exceeding the rating of the associated unidirectional currentflow means, said power relay comprising a second energizing coilconnected in parallel with a unidirectional current flow means, a secondmobile armature actuatable by said second coil, a power circuitincluding said armature, and said power circuit connecting said transfermeans to the electrical power source.

5. An electrical level-correcting device according to claim 4 whereinsaid switching means comprises a main switch actuated by saidaccelerator and a normally closed slow-acting relay connected in seriesbetween said main switch and said transfer means, said re-feed relay inits closed position by passing said slow-acting relay.

No references cited.

BENJAMIN HERSH, Primary Examiner. M. S. SALES, Assistant Examiner.

1. IN A VEHICLE HAVING A BODY, AN ACCELERATOR PEDAL, WHEELS AND A FLUIDSUSPENSION SYSTEM, AT LEAST ONE SUSPENSION ELEMENT ASSOCIATED WITH EACHWHEEL FOR SUPPORTING SAID BODY, ELECTRICALLY ACTUATED TRANSFER MEANS FORCONTROLLING AN ACTIVE FLUID MASS ENCLOSED WITHIN SAID ELEMENT, ANELECTRICAL LEVEL-CORRECTING DEVICE COMPRISING, IN COMBINATION, AWHEEL-SWITCH ASSOCIATED WITH EACH WHEEL FOR DETECTING THE POSITIONTHEREOF RELATIVE TO SAID BODY AND FOR CONTROLLING THEREBY THE ACTUATIONOF SAID TRANSFER MEANS, IMPULSE-PRODUCING MEANS COMPRISING SWITCHINGMEANS AND AN ELECTRIC POWER SOURCE, SAID IMPULSE-PRODUCING MEANSCONNECTING SAID WHEEL SWITCH TO SAID ELECTRIC POWER SOURCE ONLY ATSELECTIVE INTERVALS, A RE-FEED RELAY OF THE NORMALLY OPEN TYPE HAVING ANENERGIZING COIL AND A MOBILE ARMATURE ACTUATABLE BY SAID COIL, SAIDARMATURE IN ITS CLOSED POSITION BY-PASSING SAID IMPULSE-PRODUCING MEANSBY CLOSING A CIRCUIT BETWEEN SAID POWER SOURCE AND SAID WHEEL SWITCH, ATLEAST ONE UNIDIRECTIONAL CURRENT FLOW MEANS CONNECTING SAID ENERGIZINGCOIL TO EACH AND EVERY ONE OF SAID TRANSFER MEANS FOR PROVIDINGENERGIZATION OF SAID COIL AT THE SAME TIME AS ANY ONE OF SAID TRANSFERMEANS BUT PREVENTING STRAY SIMULTANEOUS ENERGIZATION OF SEVERAL TRANSFERMEANS.